The Uskok War, also known as the War of Gradisca, was fought by the Austrians and Spanish on one side and the Venetians, Dutch and English on the other. It is named for the Uskoks, Croatian soldiers used by the Austrians for irregular warfare.

The Uskok War, also known as the War of Gradisca, was fought by the Austrians and Spanish on one side and the Venetians, Dutch and English on the other. It is named for the Uskoks, Croatian soldiers used by the Austrians for irregular warfare. Since the Uskoks were checked on land and were rarely paid their annual salary, they resorted to piracy. In addition to attacking Turkish ships, they attacked Venetian merchantmen. Although the Venetians tried to protect their shipping with escorts, watchtowers and other protective measures, the cost became prohibitive: 120,000 Thalers annually during the 1590s, 200,000 in the 17th century and 360,000 by 1615.:36 In December 1615 Venetian troops besiegeed Gradisca, on the Isonzo River. The Venetians launched a diplomatic campaign for allies, since the Uskoks were vassals of Archduke Ferdinand of Inner Austria (who was likely to seek help from the Holy Roman Emperor Matthias—his uncle—and King Philip III of Spain, his brother-in-law. In September 1616, Count John Ernest of Nassau-Siegen agreed to raise 3,000 men in the Dutch Republic for Venetian service. They arrived in May 1617, followed six months later by another 2,000 with a contingent of English volunteers. Spanish support was blocked at sea by a flotilla of 12 Dutch and 10 English warships, and on land by the war in Mantua.:36 (en)

The Uskok War, also known as the War of Gradisca, was fought by the Austrians and Spanish on one side and the Venetians, Dutch and English on the other. It is named for the Uskoks, Croatian soldiers used by the Austrians for irregular warfare. (en)